Means for and methods of washing debris from tubular goods in wells



A1311! 8, 1958. G HOUSE ETAL 2,829,715

MEANS FOR AND METHODS OF WASHING DEBRIS FROM TUBULAR GOODS IN WELLS Filed Oct 4. 1954 W////am M Burnezz G/e/vrl C. House IN V EN TORJ BYT United States Patent MEANS FOR AND METHODS OF WASHING DEBRIS FROM TUBULAR GOODS IN WELLS Glenn c. House and William M. Burnett, Houston, Tex., assignors to Wesley West, Houston, Tex.

Application October 4, 1954, Serial No. 460,072

6 Claims. (Cl. 166-44) This invention relates to means for and methods of washing debris from tubular goods in wells, and more particularly to means for and methods of accomplishing circulation of liquid inside of tubular goods in a well when ports in such tubular goods are blocked.

While this invention is the product of work on problems in the drilling of oil wells, it is obvious that it may also be used in other drilling operations and wherever it is desired to wash the inside of a deep recess in an inaccessible place. But, for purposes of explanation, consider a particular problem in connection with drilling wells. In this connection, the apparatus used may be characterized as a wire line circulating tool.

In drilling wells by the rotary tool method, a drill bit is secured to the lower end of a string of tubing, commonly referred to as the drill string, and is lowered into the hole. Drilling is accomplished by rotating the drill string and the bit secured thereto. Cuttings are removed from the hole by the circulation of some liquid, such as drilling mud, into and down the drill string, out of ports in the bit, and up through the annular space between the drill string and the wall of the hole. The drilling mud picks up the cuttings as it emerges from the ports in the drill bit and carries the cuttings to the surface.

The drill bit has a conduit from the top thereof to the ports referred to, and thereby constitutes a form of tubular goods. The lower end of the drill string is frequently formed from so called drill collars, being lengths of exceptionally heavy drill pipe with somewhat smaller internal diameter than the normal drill pipe which makes up the bulk of the drill string. The drill bit and any length or lengths of drill collars or other drill pipe to which it may be attached are therefore also seen to constitute tubular goods and they will be so referred to elsewhere in this specification.

It frequently occurs in drilling operations, that the drill bit gets stuck in the bottom of the hole and, for one reason or another, the bit and/or the bottommost lengths of drill collars become clogged with sand and other debris. Before circulation can be restored through the drill bit, this debris must be cleaned out. In accordance with this invention, this cleaning is accomplished by establishing circulation into and out of the same end, the open end, of the clogged drill collars. The debris can thereby be washed out of the drilling fluid conduit in the inside of the drill collars.

It is obvious that substantially the same problem may arise when production tubing or other tubular goods be comes clogged at the bottom of a hole, or in any operation when there is a small recess in some inaccessible location, which must be washed out. For purposes of the remainder of this specification, such clogged tubing or recess will be referred to as tubular goods, as distinguished from other pipe tubing used in connection with this invention.

By way of further explanation of the problem, it might be noted that when a drill string is stuck and the lower 2,829,715 Patented Apr. 8, 1958 end thereof is bound and secured by sand and other debris, the drill string may be parted, by means well known in the art, at any selected joint, such as the joint immediately above the clogging, and the upper portion of the drill string may then be withdrawn. In accordance with this invention, it is necessary to part the selected joint and withdraw the upper portion of the drill string only a few inches before the cleaning operation can be commenced, Whereas in other efforts to clean out clogged tubular goods it is necessary to withdraw the entire drill string.

Those familiar with oilfield operations will know how a string of pipe may be broken at a predetermined joint.

For example, the weight of all the pipe above the desired breaking point is calculated, and the top of the string is pulled upward with a force sufficient to counterbalance Thus, all joints above the one to be brokenhave tension stresses on them, and any joints below the.

this weight.

one to'be broken have compressive stresses from the weight of the pipe below the joint being broken. The joint being broken, has a minimum of either tension or compressive stress thereon. An explosive, frequently in the form of a cord, is run into the string and. positioned at the joint to be broken. The pipe at the surface is backed off enough to place the entire string under back- The explosive is fired and the desired into the well and so located as to leave a space or open-,

ing between the tubular goods to be washed and the drill string or other tubing which is to be used to define the washing liquid conduits to the proximity of the clogged tubular goods or other recess. For purposes of this specification, the drill string or other pipe or tubing which is used to define the washing liquid conduits to the proximity of the clogged tubular goods, is hereinafter referred to as tubing, as distinguished from the tubular goods to be" washed and tubular elements in this invention.

As is apparent from the foregoing discussion, an object of this invention is to provide improved means for and method of washing out tubular goods which are clogged, or any other recess which is inaccessibly located.

Another object of this invention is to provide improved means for and method of so washing debris from tubular goods which is convenient and quickly and easily ac complished.

A further object of this invention is to provide improved means for and method of so washing debris from tubular goods stuck in a hole which does not necessitate the removal from the hole of an entire string of tubing.

Others objects are apparent from the following description and accompanying drawings wherein:

Figure 1 is an elevational section of a well with a drill string and a preferred form of the invention positioned therein.

Figure 2 is an elevational section of a large casing with tubular goods to be washed and washing fluid conduit tubing positioned therein, together with another preferred embodiment of the invention.

The casing 1, in Figure 2, functions in the same mam ner as the wall 2 of the hole in Figure l. Tubular goods 3, which are to be washed, are shown in the casing 1 near the lower end thereof. Sand, rock, shale and other debris 4 are shown in the tubular goods 3.

Above the tubular goods 3, there is tubing 5 which defines, internally thereof, the downward path 6 for the washing fluid, for example drilling mud, and which do; fines, in cooperation with the casing 1, the upward or return path 8 for the washing fluid between the tubing and the casing 1. Between the tubing 5 and the tubular goods 3, there is a space 10 which constitutes a port permitting fluid flow into the return path 8.

In accordance with this invention, a length of pipe 12 of sufficiently small diameter to permit its free passage through the tubing 5 and into the tubular goods 3, is suspended from a wire line 14. The pipe 12 is preferably provided with a tough blade or point 16 at the lower end thereof which is able to withstand being dropped into the debris or sand 4.

The pipe 12 is also provided with ports 18 at the upper end thereof, and ports 19 at the lower end or in the point 16. Washing fluid may thereby be conducted down the path 6 inside the tubing 5, into the upper ports 18, down the pipe 12, and out the lower ports 19 at or near the sand 4. The turbulence of the washing fluid as it emerges through the lower ports 19 causes it to pick up sand and carry the sand upward through the annular space I between the pipe 12 and the tubular goods 3, out the 1 pass internally therethrough. While packing means of various sorts may be used, such means are subject to many unsatisfactory features.

In accordance with this invention, it is preferred to accomplish the proper direction of the flow of washing fluid by predetermining the resistance to fluid flow external of the upper end of the pipe 12 to be of substantial magnitude in comparison with the resistance to fluid flow through the pipe 12. This is accomplished by predetermining the annular space 20 between the pipe 12 and the tubing 5 to be of relatively small cross section and of substantially greater length than the length of the annular space 21 between the pipe 12 and the tubular goods 3. Also the annular space 20 is smaller in cross section than the conduit down the inside of the pipe 12. The resistance to fluid flow through the length of the annular space 20 may thereby be made to be equal to, or greater than the resistance to fluid flow through the pipe 12, out the lower ports and up the annular space 21. Of course, it is preferable that the resistance to fluid flow through the annular space 21 be as much greater than the resistance to flow through the pipe 12, as is possible.

It is accordingly preferable to have the length of the annular space 20 as great as is practical, and its cross section as small as is practical, while the annular space 21 should be as short in length and as large in cross section as is practical. The inclusion of small annular shoulders (Figure 2) on the upper end and external of the pipe 12 is readily appreciated to constitute a form of alternative embodiment which will facilitate impedance of fluid flow through the annular space 20.

When tubing is not already in the hole, it is frequently convenient to use tubing 5 of a slightly smaller internal diameter than the tubular goods 3, thereby assuring restriction of flow external of the upper end of the pipe 12 to a greater extent than external of the lower end of the pipe 12.

Figure 1 illustrates the problem when a drill bit 24 and a length or more of drill collars 25 are clogged with sand and debris 4. The drill bit and clogged drill collars constitute tubular goods 3 which are to be washed. It frequently occurs that one or more drill. collars in the drill string are free and clean and not clogged, and the lowermost free joint is broken. The drill string, with the clean drill collars 27 on the lower end thereof, is pulled upward slightly so as to form an opening 10 between the clean collar 27 and the clogged collar 25.

Above the clean collar 27, or other collars if there be more, ordinary drill pipe 29 extends to the surface of the well. It is apparent that the drill pipe 29 and the clean drill collar 27, constitute tubing 5 with an internal shoulder 30 therein. The shoulder 30 is at the top of the first drill collar 29.

When tubing 5 with such a shoulder 30 is in the hole,

\ or can conveniently be lowered into the hole, then a second embodiment of the invention may be used. In this embodiment there is still a pipe 12, with upper ports 18 and lower ports 19. The pipe 12 is small enough to pass inside the drill collars, but it is preferred for the f pipe 12 to extend up above the drill collars into the drill pipe 29. Below the upper ports 18, an annular shoulder 32 is fitted on the pipe 12. Preferably an inverted skirt or sleeve 34 is fitted on the shoulder 32 and extends upward above the upper ports 18.

External of the skirt 34, the shoulder 32, and the upper end of the pipe 12, there are annular spaces 20. Preferably these annular spaces 20 are of smaller cross sectional area than the annular space between the skirt 34 and the pipe 12. External of the lower end of the pipe 12 there is an annular space 21.

Preferably the length and cross sectional area of the annular space21 are of such dimensions as to present relatively little resistance to fiuidflow while the length and cross sectional area of the annular spaces 21'? are of such dimensions as to present relatively great resistance to fluid flow.

In this embodiment of the inventon, there is no danger of loss of the tool in the hole because the shoulder 32 on the tool will engage the shoulder 30 of the drill collar and thereby be retained in the drill string. Conveniently flutes or grooves 36 may be cut in the lower side of the shoulder 32 to prevent an absolute stoppage of fluid flow external of the tool when the two shoulders are in contact with each other.

The pipe 12 may be made up in sections so that different lengths of pipe may be used on different jobs as the occasion demands. A swivel and jars can be run above the wire line circulating tool is deemed necessary.

It is apparent that modifications may be made in the invention as particularly described herein without departure from the scope thereof. For example, the pipe 12 may be open at the upper end instead of having ports in the side thereof at or near the upper end, the more important consideration being to have the upper ports and the lower ports spaced apart. Likewise, the opening 10 may be constituted from holes in the tubing 5 rather than from a space between the tubing 5 and the tubular goods 3. Accordingly, this description is to be taken as illustrative only, and is not to be construed as a limitation upon the invention as defined in the following claims.

We claim:

1. The method for establishing circulation within tubular goods located in a well and clogged at the lower end with debris, comprising the steps of positioning tubing in the well above such tubular goods with the lower end of the tubing adjacent but spaced upwardly from the open top of the tubular goods whereby an annular space is provided between said tubing and tubular goods for outward flow of fluid; lowering into said tubing and tubular goods on a line a tubular member the outer diameter of which is smaller than the inner diameter of said tubing and smaller than the inner diameter of said tubular goods, said tubular member having at least one opening at each of its ends, whereby liquid can flow through such tubular member, the length of said tubular member being such that when the lower end thereof is disposed in proximity to debris in the lower end portion of the tubular goods the .upper end of said tubular member occupies a position within said tubing substantially above said annular space,

ing downwardly through said tubular member into (7011-,

tact with the debris and thence upwardly through said tubular goods outside of said tubular member and then outwardly through said annular space, whereby the debris is washed from the tubular goods, and with the liquid also flowing downwardly through the space between said tubing and said tubular member and thence outwardly through said annular space.

2. The method of claim 1 including the further step of periodically vertically reciprocating said tubular member with the lower end thereof in engagement with the debris for at least part of such reciprocation.

3. The method for establishing circulation within tubular goods located in a well and clogged at the lower end thereof with debris, comprising the steps of positioning tubing in the well above such tubular goods with the lower end of the tubing adjacent but spaced upwardly from the open top of the tubular goods, whereby an outflow space is provided between said tubing and said tubular goods; then establishing within the lower portion of said tubing two concentric open-ended fluid-confining flow channels directed toward said tubular goods with the outer one of said channels presenting a greater resistance to downward fluid flow than is presented by the inner one of said channels, with said outer channel communicating directly with said outflow space, with said inner channel extending below said outflow space into said tubular goods to terminate in proximity to the debris and with said inner channel being of smaller cross-section than the space within the tubular goods; and then pumping liquid downwardly Within said tubing from a point above said channels and thereby causing fluid to flow downwardly through said inner channel into contact with the debris and thence upwardly within said tubular goods and outwardly through said outflow space while fluid is also flowing downwardly through said outer channel and outwardly through said outflow space.

4. In apparatus for washing debris from within tubular goods in the bottom of a Well when the top of such goods is open, the combination of tubing disposed within the well and extending downwardly to a point adjacent to said top but spaced thereabove to provide an outflow space communicating both with the interior of said tubular goods and with the interior of said tubing, an elongated tubular member having an opening at each end and being of such length that when one end thereof is disposed in the lower portion of said tubular goods the other end is disposed within said tubing at a point substantially above said outflow space, said tubular member being smaller in cross-section than the inner diameter of said tubing and also smaller in cross-section than the inner diameter of said tubular goods; and means extending from the top of the well and supporting said tubular member within said tubing and tubular goods with the lower end of said tubular member in proximity with the debris, whereby two concentric fluid fiow channels are provided, the outer one of which leads downwardly to said outflow opening and the inner one of which extends into proximity with the debris, said outer channel presenting a greater resistance to downward fluid flow than is presented by said inner channel, whereby fluid pumped downwardly in said tubing from a point above said tubular member will flow not only through said outer channel and thence out said outflow space but also through said inner channel into contact with the debris and thence upwardly within the tubular goods and out said outflow space.

5. The apparatus of claim 4 including fluid flow restricting means carried by said tubular member at a point intermediate of its length and extending outwardly toward said tubing.

6. The apparatus of claim 4 wherein the outer surface of said tubular member is a plane, substantially uninterrupted surface and the cross-sectional area of said outer channel is smaller than the cross-sectional area of said inner channel.

References Cited in the file of this patent UNITED STATES PATENTS 1,824,283 Marr Sept. 22, 1931 1,989,035 Blum Jan. 22, 1935 2,212,491 Appleby Aug. 27, 1940 2,289,755 Chamberlain'et al July 14, 1942 2,687,774 Hodges Aug, 31, 1954 

